Update teleport to use four separate reference spaces

Since reference spaces are only valid for a given session, the
non-immersive (magic window or identity) and immersive reference
spaces need to be saved separately. We also need to separately
store and use offset reference spaces, and recalculate them
from the appropriate base un-offset reference space as needed.

Change-Id: I4ef53e8d0b5af617f1a348ccf24e885656806b8e
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1618241
Reviewed-by: Brandon Jones <bajones@chromium.org>
Commit-Queue: Klaus Weidner <klausw@chromium.org>
Cr-Commit-Position: refs/heads/master@{#661913}
1 file changed